Past-month cannabis consumption by teenagers fell significantly last year and is lower than it was before legalization.

In its latest report on marijuana legalization in Colorado, the Rocky Mountain High Intensity Drug Trafficking Area (RMHIDTA), a federally sponsored anti-drug task force, continues to claim that cannabis consumption by teenagers is on the rise in that state. The most recent data from the survey RMHIDTA likes to cite indicate that is not true.

"Youth past month marijuana use increased 12 percent in the three-year average (2013-2015) since Colorado legalized recreational marijuana compared to the three-year average prior to legalization (2010-2012)," RMHIDTA says. But according to newly published Colorado numbers from the National Survey on Drug Use and Health (NSDUH), the prevalence of past-month marijuana use among 12-to-17-year-olds fell significantly in 2015-16 and is now lower than it was prior to legalization.

NSDUH

That rate rose from about 10.5 percent in 2011-12, before legalization, to 11.2 percent in 2012-13, which includes the first year of legal possession and home cultivation, and 12.6 percent in 2013-14, which includes the first year of legal recreational sales. (The numbers are reported in two-year sets because the state-level samples are relatively small.) The post-legalization increases were not statistically significant, and the rate now has fallen for two years in a row, to 11.1 percent in 2014-15 and 9.1 percent in 2015-16. That last drop was statistically significant.

The numbers for Washington state, where voters also approved a legalization initiative in November 2012, show a similar pattern, rising from 9.5 percent in 2011-12 to 10.1 percent 2013-14 before falling to 9.2 percent in 2014-15 and 7.9 percent in 2015-16. Unlike in Colorado, neither of those drops was statistically significant.

As I've said before, it is plausible that legalizing marijuana for adults would boost adolescent consumption by increasing availability through diversion from buyers 21 or older, if not by changing teenagers' attitudes toward cannabis. But there is still little evidence that is happening, notwithstanding the assertions of prohibitionists like the folks at RMHIDTA.

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I’m too lazy to read the survey methodology, but I wonder if it’s wrong. My daughter who’s in high school says pot is pretty much everywhere among her classmates. I’m wondering if the culture of legalization caused those being questioned on the survey to self report lower incidents of consumption. I would have no idea why, but there might be some interesting psychological changes in viewpoint that could be skewing the numbers.

This is a big fear, I’ve noticed. That legalization will lead to higher usage rates amongst teens. My question is, why should we care? People want to regulate it like alcohol, but I’m not sure it matters much at all.

I don’t care, but the people doing the survey seem to… and as best I can tell, Reason seems to. I mean, I guess heavy marijuana usage among teens might be something to be concerned about, I just wonder if the survey results are wrong.

Maybe now that it is legal and regulated it feels more like a sting when you are asked about your usage

That’s almost exactly what I’m wondering. It’s legal, but underage people are specifically singled out as still being outside the law of they consume it. Honestly, I’m surprised anyone answered honestly ever, especially when it was illegal.

I mean, I guess heavy marijuana usage among teens might be something to be concerned about, I just wonder if the survey results are wrong.

Also without reading the methodology, smoking is, to a degree, still smoking and it’s pretty clear that we conceptually transfer the animism of smoking to things that are much less smoking/tobacco related. Not that I or Reason or whomever is advocating for state intervention but half the boogeyman that was smoking was ‘The Big C’ and there’s every indication that a joint-year (however fuzzily you may define that) is pretty directly interchangeable with a pack-year.

That is to say, a 19-yr.-old picking up ‘the habit’ because his friends offered him some and/or he caught his parents one weekend is a different proposition than the 13-yr.-old picking up ‘the habit’ because mom and dad have been stoned as long as they can remember.

From what I have seen and read, Amsterdam experienced the same thing when they made weed basically legal. And, it kind of makes sense when you think about the fact that some of the appeal to young people is that it’s a rebellious act. But, once you legalize it, it kind of makes it boring.

Next time, ask her to count, and about verified numbers. I’m going to bet that it’s a mix of kids lying to seem cooler then they are (similar to how kids have always lied about sex, drugs and alcohol) and that humans are terrible at guessing proportions.

One of the memes floating around the debate in NJ and PA over legalization is that “motor vehicle deaths due to marijuana use have soared in Colorado.” Any evidence, one way or another, that this is true? I know lots of people who don’t give a damn if someone smokes weed at home but are scared to death of more stoned drivers, therefore we have to keep banning it.

The number of drivers involved in fatal crashes in Colorado who tested positive for marijuana has risen sharply each year since 2013, more than doubling in that time, federal and state data show. A Denver Post analysis of the data and coroner reports provides the most comprehensive look yet into whether roads in the state have become more dangerous since the drug’s legalization.

Increasingly potent levels of marijuana were found in positive-testing drivers who died in crashes in Front Range counties, according to coroner data since 2013 compiled by The Denver Post. Nearly a dozen in 2016 had levels five times the amount allowed by law, and one was at 22 times the limit. Levels were not as elevated in earlier years.

Some newspapers and news shows played up a story that contends legalized marijuana has made our roads and highways less safe. It may sound plausible, but the facts don’t support this assertion. In fact, marijuana legalization has not increased overall traffic fatality rates nor the total number of non-fatal crashes, according to two separate studies conducted by Columbia University and the University of Texas-Austin.

Additionally, Colorado State Patrol reports a decrease in the number of driving impaired accidents since marijuana sales became legal.

Despite this academic research and on-the-ground expertise from state police, it was a study from a group supported by auto insurers last week that captured the most ? and loudest ? headlines. “Car crashes leap in states with legalized marijuana,” was just one of many headlines characterizing The Highway Loss Data Institute’s (HLDI) finding that three states where marijuana is legal ? Colorado, Washington and Oregon ? had an increase in traffic accidents.

Not saying one way or the other regarding whether pot causes crashes, but the tests are pretty useless for determining if someone is currently high?. All they really tell you is that someone was high, sometime in the last two weeks (or months). ________ ?Unless they have a new fancy test I haven’t heard of yet.

Given that usage seems to be roughly stable, I’d guess it’s because more of the previous users are using high-THC shit that’s showing up in blood tests more easily.

Iron Law of Prohibition: banning something reduces its quality relative to its quantity. Prohies assume this means less quantity, but with pot and other drugs it seems to reduce quality while leaving quantity unchanged. With opioids, that means heroin and fentanyl (and 10s of 1000s of unnecessary deaths); with weed, that meant shittier grows that leave the bloodstream faster.

not valid. Graph doesn’t present data relative to population change or miles driven. Seems to me that auto accidents are relatively flat before and after legalization. Are alcohol sales down during this period?

Whatever Mom and Dad do recreationally, the kids aren’t very likely to want to try. How many hardcore smokers had parents that smoked when they were young and living with them? Not very many. Most of them loathe smoking.

And as I’ve said before, if you want to find pot, ask a teenager. I have never used pot, but as a teen I could have purchased half a lid on 30 minutes notice. As an old fart, I’d need to spend a day asking around just to find a connection.